Secured Keypad Devices

1. A data entry device comprising: a housing including a top housing portion including key apertures; a key assembly including a plurality of depressible keys, which partially extend through said key apertures and key contacts which do not underlie said key apertures; a protective partial enclosure at least partially surrounding said key assembly, said protective partial enclosure including at least one anti-tampering grid formed of a multiplicity of interconnected anti-tampering electrical conductors and being formed with apertures aligned with said key apertures for permitting displacement of said depressible keys therethrough; wherein said key contacts underlie said at least one anti-tampering grid; wherein said key assembly is constructed such that said key contacts define an open electrical circuit when a key of said depressible keys is depressed and define a closed electrical circuit when a key of said depressible keys is not depressed; and wherein said protective partial enclosure includes a top anti-tampering grid overlying said key assembly and having grid apertures aligned with said key apertures and said protective partial enclosure includes a bottom anti-tampering grid underlying said key assembly.

2. The data entry device according to claim 1 and wherein said key assembly is constructed such that said key contacts define the closed electrical circuit when a key is depressed and define the open electrical circuit when a key is not depressed.

3. The data entry device according to claim 1 and wherein said key assembly further includes a printed circuit board and a plurality of depressible key elements which are displaceable relative thereto, said printed printing circuit board defining a first key contact for each of said depressible key elements, which does not underlie a corresponding key aperture and each of said plurality of depressible key elements defining a second key contact, which does not underlie a corresponding key aperture, for selectable engagement with said first key contact.

4. The data entry device according to claim 1 and wherein said anti-tampering electrical conductors are electrically connected to anti-tampering detection circuitry.

5. The data entry device according to claim 1 and wherein said key contacts do not underlie said grid apertures.